Bank nifty has reversed from 1.618FE of wave 1. IF it takes support at the 38% or 50% fib levels (and the trendline ), then it could result in a sharp up move to new highs. This should pull Nifty too; just that the wave structure is clearer here.
(Support at the 23% fib level for the up move after that is possible too but then an initial entry would be difficult to perceive.)

Comment:
SL would be just below the 50% fib retracement. (Going below it would negate the above. )